Distributing-valve for hydraulic speed-regulators.



R. THOMANN.

DISTRIBUTING VALVE FOR HYDRAULIC SPEED REGULATORS. APPLICATION rum) NOV.13, 1902.

N0 MODEL.

PATBNTED JULY 21, 1903.

2 SHEETS-SHEET 1-.

A I r I- I I WITNESSES mvmron ATTORNEYS.

'PATENTED JULY 21-, 1903.

R. THOMANN. DISTRIBUTING VALVE FOR HYDRAULIC SPEED REGULATORS.

APPLICATION FILED NOV. 13, 1902.

2 SHEETS-SHEET 2.

\ H0 MODEL.

ATTDRNE rs.

- UNITED I S E Patented July 21, 1903.

PATENT OFF-Ice.- I

ROBERT THOMANN, OF TUTTGART, GERMANY, ASSIGNOR TO J. M. VOITII,

' OF WURTEMBERG, GERMANY, A FIRM.

DISTRIBUTING-VALVE FOR HYDRAULIC SPEED-REGULATORS.

SPECIFICATION forming atter Letters latent No. 734,285, dated July 21,1903.

Application filed November 13, 1902. Serial No. 13l,l29. (No model.)

This invention relates to hydraulic speed 2o regulators, and moreespecially to an improved valve-gear for distributing-valves forhydraulic speed-regulators by which the power necessary for the movementof the regulating piston-valve and the reaction on 15 the gearing isvery small and by which the relative pressure which exists between thetwo faces of the piston-valve is changed in such a manner by the use ofan actuating piston-rod loosely connected therewith that the supply ordischarge of the medium acting on the faces of the piston-valve isregulated by the pistonrod.

and its piston-rod does the regulator-piston find itself in equilibrium;but as soon as a shifting of the piston rod takes plaoe the piston-valvehas immediately the tendency to follow it until it assumes again itsposition of equilibrium. 7 1

is that by the use of thesame'the reaction on the gearing is verysmallandthatb y the least displacement of the piston-rod bythe governormechanism the piston-valve will 3 5 follow the same by means of the highpower exerted by the pressure fluid. complished by a double action ofthe valve and by causing the distributing-channels to pass completely inthe piston-valve, and thus 40 make them necessarily very short.

For carrying out these effects the invention consists in adistributing-valve for hydraulic speed-regulatorscomprisin g avalvechest provided with a supply-pipe, outletchannels anddischarge-channels, a pistonvalve in said-valve-chest provided with acentral bore, a shiftable piston-rod passing through the central bore ofthe piston-valve and of smaller diameter than said bore, so as to forman annular channel around the same,

and shoulders on said piston-rod which by Only in one determinedrelative position of the'piston-valve An essential feature of; myimproved valve This is ac-' opening or closing the annular channelchange the-amount of pressure fluid in the spaces between the heads ofthe piston-valve and chest, as will bemore fully described hereinafter,and finally pointed out in the claim.

In the accompanying drawings, Figure 1 represents a side elevation,partly in vertical section, of my improved hydraulic speedregulator,showing its connection with a centrifugal governor and so-calledservomotor of a turbine. Fig. 2 is a side elevation of thedistributing-valve of the same. Fig. 3 is a vertical central section ofthe distributing- 6 5 valve, drawn on a larger scale; and Fig. at is asimilar section of a slightly modified con structionof the same.

Similar letters of reference indicate corresponding parts.

In the drawings, A represents the distributing-valve, O the servomotoror cylinder connected therewith, and q a centrifugal governor connectedwith the piston-rod of the distributing-valveA. The pressure medium orfluid which drives the servomotor O is supplied through the pipe to intoa central channel h (shown in Figs. 3 and at) of the cylindricaldistributing-valve, while the discharge of the pressure fluid isaccomplished through the channel land pipe t. According to the positionof the balanced piston-valve g'the pressure fluid will pass either fromthe channel h into the channel 70 or from the channel 7 into the channel2'. The lapping over of the piston-valve g is so calculated that thechannel k or i which is not in connection with the central chamber 71 isin communication with the discharge-channelZ. \Vhen the pressure fluidenters into the channel 70, the movement of the servomotor takes placein an opposite direction from that which it assumed when the pressurefluid enters to the same-through the channel 1 as shown in Fig. 1. Inthe balanced piston-valve g is loosely placed the piston-rod f, whichacts as a regulating rod or spindle and which is actuated by means of acentrifugal governor q. i

In the construction of the distributingvalve (shown in Fi 3) thechambers 12 and b,

between the ends of the valve-casing and the faces of the piston-valveg, are connected by an annular channel (1, which is formed around thepiston-rod f by slightly diminishing the diameter of the same within thepiston-valve, said spaces being filled with the pressure fluid throughspecial supply-channels act,arranged in the ends of the casing. Thechannel d is constantly connected with the dischargechannel Z by meansof the lateral openings 6 c. The piston-rod f has projecting shoulders c0, one adjacent to each face of the piston-valve and at a distance fromeach other which is somewhat greater than the length of the balancedpiston-valve g, so that when the balanced piston-valve is in its normalposition relatively to its piston-rod the spaces 1) Z) are connected bytwo equal narrow annular channels with the channel (Z and thedischarge-channel l, whereby the pressure in the spaces 1) and b isequalized. As soon as the piston-rod f makes the smallest movementforinstance, in downward directionthe upper ring-shaped channel at theshoulder 0 will be contracted or entirely closed. In consequence of thisthe pressure in the chamber 1) in contrast to the pressure in thechamber 7) will be increased, so that the piston-valve Q will be presseddownwardly until it assumes again its normal median position ofequilibrium between the shoulders c and 0. Thus the balancedpiston-valve 9 follows the slightest movement of the piston-rod fwithout producing any reaction on the connectingrods of the gearing oron the sleeve 1) of the governor.

In the modified construction shown in Fig. at the narrow channel (Z,which connects the chambers b b, is not connected with thedischarge-channel, but with the inlet-channel h by means of openings aat the center of the piston-valve g. The spaces Z) I) are connected withthe discharge-channel Z by means of small channels 6 c in the ends ofthe pistonvalve. The piston-rod f in this case has near its centershoulders c c, forming an enlarged portion, which when the balancedpistonvalve 9 is in its normal position will completely cover theopenings a so that the pressure fluid coming from the chamber it cannotpass to either one of the chambers b b. In consequence of this thereexists in the spaces 1) b under normal conditions one and the samepressure, which is equal to the pressure in the discharge-channel of thedistributing-valve. As soon as the pistonrod f makes the smallestshifting movement-for instance, in upward direction-the pressure fluidcoming from the chamber h will be permitted to pass along the shoulder 0into the channel (I and into the chamber 1), so that the pressure in thespace I) as compared with the pressure in the chamber 11 will beillcreased, whereby the piston-valv'e will be raised until the opening ais againclosed. In a similar manner the piston-valve will follow anydownward movement of the pistonrod f.

In Figs. 1 and 2 are shown the connection of the distributing-valve Awith the governor g and with the servomotor O, which latter is driven bythe pressure fluid and which operates the regulating-shaft or otherspeed-regulating organ of a turbine. The piston-rod f of thedistributing-valve A rises and falls with the falling and rising of thesleeve of the governor q, the spindle of which receives its motion fromthe turbine. Channels 7t and 'i are connected by the conducting-pipes 1"and s with the opposite ends of the cylinder of the servomotor 0, whilethe supply-channel his connected with the supply-pipe u and theoutlet-channel Z with the discharge-pipe t. The two supply-openings aand a, leading to the spaces Z1 and Z), are connected with thesupply-pipe u by means of the branch pipes 00 and y. The piston-rod o ofthe servomotor O governs in the well-known manner the regulating membersof a turbine. In Fig. 1 the piston of the servomotor is shown in itsdownward course in the direction of the arrow. The piston-rod f is shownin raised position, compared to its position shown in Fig. 3, inconsequence of the lowering of the governorsleeve; The piston-valve ghas followed the piston-rod f, so that the pressure fluid can pass fromthe channel h to the upper outletchannel i and through the pipe 5 to thespace above the piston of the servomotor, while the space below thepiston is connected by means of the pipe 1' with the channel 70,outlet-channel Z, and discharge-pipe t.

The operation of the improved valve-gearing is the following: Theturbine is supposed to be running with its rated speed, the centrifugalgovernor q being connected with the turbine. The piston-rod o of theservomotor is connected to the regulating member of the turbine. \Viththe turbine running at its normal speed the pressure of the fluidflowing continually from the supply-pipe u and channel h to thedischarge-channel l and discharge-pipe zis the same in the chambers 11and b, and no action of the regulating-piston f and valve g on thepiston of the servomotor takes place. When, however, the turbine, due toincrease of load or otherwise, should diminish its speed, fly-balls ofthe governor q will fall. The sleeve 1) will consequently be lowered, soas to raise the pistonrod f. This will cause a contraction of theannular channel formed between the shoulder a of the piston f and thelower end of the valve g. The fluid in space 0 will be forced throughchannel (1, channel 6, and outlet-channel Z to the discharge-pipe t. Thepressure fluid entering through channel a into the space I), owing tothe contraction of the annular opening 1;, will force the piston-valve gin upward direction. This permits the pressure fluid entering bysupply-pipe u and channel h to flow through channel 1' and pipe 8 intothe upper part of the cylinder of the servomotor 0 and force the pistonof the servomotor in downward direction. The fluid in the lower part ofthe cylinder of the servomotor is passed off through the pipe '1",channel k,-

channel e,outlet-channel, and discharge-pipe t. The downward movement ofthe pistonrod of the servomotor O actuates the regulating member of theturbine, and consequently increases the speed of the same. The increaseof speed of the turbine raises the flyballs of the governor, thusraising the sleeve 1) and lowering the piston-rod f. This in turn causesa contraction 'of the annular channel 0, increasing thereby the pressureof the fluid in chamber 6, forcing the piston-valve g to follow themovement of the piston-rod f and either again bringing the piston-valveg to its position of equilibrium, in which case corresponding currentsof the pressure liquid, but

- an inverse motion of the piston of the servoclaim as new and desire tosecure by Letters Patent- A distributing-valve for hydraulicspeedregulators, comprising a valve-chest provided with a supply-pipe,outlet-channels and dis- 3o charge-channels, a piston-valve in saidvalvechest provided with a central bore,a shiftable piston-rod passingthrough the central bore of the piston-valve and of smaller diameterthan the said bore so as to form an annular 35 channel, channelsconnecting said annular channel With the discharge channel, andshoulders on said piston-rod, which by open ing or closing the annularchannel, change the amount of pressure fluid in the spaces be- 0 ROBERTTIIOMANN.

Witnesses KARL ZIETRICH, WM. HAHN.

